Radio Frequency Identification (RFID) tags contain at least two parts: first, an integrated circuit for storing and processing information, modulating and demodulating a radio-frequency (RF) signal, collecting DC power from the incident reader signal, and other specialized functions; and second, an antenna for receiving and transmitting the signal.
Radio Frequency Identification (RFID) tags are capable of uniquely identifying an object via a pre-programmed response when queried by an external radio frequency wave. However, not all RFID tags are the same, as some are equipped with a transponder ID (TID) by the manufacturer. This TID is usually written to a chip at the point of manufacture, and not alterable. Additionally, some ultrahigh-frequency (UHF) tags can store a 64-bit, 96-bit or 128-bit serial number. These can be read-only or read/write. Others also have blocks of user memory that can be written to and locked, or rewritten over and over.
Signaling between the reader and the tag is done in several different incompatible ways, depending on the frequency band used by the tag. Tags operating on LF and HF frequencies are, in terms of radio wavelength, very close to the reader antenna; less than one wavelength away. In this near field region, the tag is closely coupled electrically with the transmitter in the reader. The tag can modulate the field produced by the reader by changing the electrical loading the tag represents. By switching between lower and higher relative loads, the tag produces a change that the reader can detect. At UHF and higher frequencies, the tag is more than one radio wavelength from the reader and it can backscatter a signal. Active tags may contain functionally separated transmitters and receivers, and the tag need not respond on a frequency related to the reader's interrogation signal.
An RFID system uses RFID tags that are attached to the objects to be identified. In operation, an RFID reader sends a signal to the tag and reads its response. The readers generally transmit their observations to a computer system running RFID software or RFID middleware.
The RFID tag's information is stored electronically in a non-volatile memory. The RFID tag includes a small RF transmitter and receiver. The RFID reader transmits a radio signal to interrogate the tag. The RFID tag receives the message and responds with its identification information.
RFID tags can be passive or active. Tags may either be read-only, having a factory-assigned serial number that is used as a key into a database, or may be read/write, where object-specific data can be written into the tag by the system user.
Although RFID tags have been used in golf balls previously, there continues to be problems with separation between the antenna portion and the RFID integrated circuit. When the RFID antenna is separated from the RFID integrated circuit, the RFID golf ball cannot be read. Additionally, RFID golf balls appear to have a noticeably different trajectory when struck than a standard golf ball.